Lawn-mower sharpener.



J. HINEMAN.

I AWN MOWER SHARPBNER. APPLICATION IILBIi AUG.17, 1914.

Patented Jan. 12, 1915.

i ii! IIIIIHI Elf 6772251" THE NORRIS PETERS 60., PHOTO-LITHO.. WASHINGTON, D. c

JQHNHINEMAN, 0F CEDAR RAPIDS, IoWA.

LAWN-MOWER SHARPENER,

Specification of Letters fatent. I P t ted J 12, 1915 Application filed August 17, 1914. Serial No. 857,252.

To all whom it may concern Be it known that 1, JOHN HINEMAN, a citizen of the United States, residing at Cedar Rapids, in the county of Linn and State of Iowa, have invented certain new and useful Improvements in Lawn-Mower Sharpeners; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to lawn mower sharpeners of the type shown and described in Letters Patent No. 1,103,581, issued to me on the 1 1th day of July, 1914, and the object of this invention is to improve the construction of such sharpeners so as to render them more adaptable to mowers of various styles and sizes, and better fitted to perform their proper functions than the device of the patent above referred to.

The nature of the improvement will clearly appear in the description and claims following, reference being had to the accom-. panying drawing, in which- Figure 1 is a cross section of a device embodying my invention as applied to amower. Fig. 2 is a rear view of the sharpening device detached.

In the drawing, 1 designates the rotary cutter-head of a lawn mower of a familiar type, provided with the usual curved blades 2. To the cross-bar 3 of the main frame is secured the ledger-blade 4: with which the rotary cutter cotiperates. A cross-rod 5 connects the housings or gear-cases 6, a construction found in almost all lawn mowers now in use or on the market. To a block 7,

which may be of wood or metal, is attached, as by screws, a slab 19 of suitable abrasive material, preferably carborumdum, with one or more straight edges to serve as the grinding surface for the revolving blades. The block is attached to the cross-bar 3 by a pair of hook-bolts 8 provided with thumb-nuts 9. The hooks of the bolts engage the flange 10 of the cross-bar, the body of the bolts passing through holes 11 in the block. To accommodate the block to various sizes of mowers,

and especially to the difl'erent widths of the cross-bars to which the ledger-blade is attached, a number of holes are provided, as

shown in Fig. 2, so that the bolts may be shifted as conditions may require. The bolts also pass through a pair of curved, flexible arms 12, terminating in hooks 13, which, when in operative position, engage the crossrod 5. In said former patent an elastic medium, such as sheet rubber, was interposed between the arms and the block to permit the block and its attached abrasive slab to yield a little. In my improved device this is dispensed with, and a simple washer 141, if anything, is interposed. The tension of the curved arms is such, however, as to tend to draw the slab toward the cutters. Itsimovement in this direction is accurately regulated by a pair of adjusting screws 15 passing through the block, and their ends abutting on the ledger-blade. In

practice the grinding edge of the slab projects inwardly a little farther than the cutting edge of the ledger-blade, which may be moved away slightly for the grinding operation. 1

An improvement in the construction of the flexible hook arms consists in forming each of two parts, one of which is slotted at 16 to take a bolt 17 provided with a thumbnut 18. By this means the arms may be lengthened or shortened according to the relative position of the cross-rod to the ledger-blade, the distance varying considerably in different sizes and makes of mowers.

In Fig. 1 the device is shown in operative position. The grinder being properly set and adjusted, the operator draws the mower in the direction indicated by the arrow, and soon brings the rotary blades to a keen and true edge adapted for perfect cutting in connectionwith the-straight edge of the ledgerblade.

Having thus described my invention, I claim:

1. A grinder for lawn-mowers, comprising a straight-edged abrasive slab, a holder bination of a straight-edged abrasive slab, a adjusting screws adapted to regulate the inholder therefor adapted to rest on the ward movement of the holder. 10 ledger-blade of the mower, hook-bolts adapt- In testimony whereof I aflix my signature ed to clamp the holder in position at one in presence of two witnesses. 5 side, curved, flexible, longitudinally adjust- JOHN HINEMAN.

able hook-arms attached to the holder and lVitnesses: t adapted to press it inwardly at the opposite J. M. ST. JOHN, side and to engage the mower cross-rod, and F. B. LEONARD.

Copies of thl-s'patent may be obtained for five cents each, by addressing the Commissioner of IEatents,

' Washington, D. C. 

